Modified README.md file

[NHartog]

Update: - Added a table of contents
- Added useful information for staging a project with Firebase
- Added a License and Contributions section to README
- Added some insight on how to debug port configuration issues in the console

This PR is solely for the documentation README.md file for the project. I have added a table of contents, more information for debugging Port issues, added a license and contribution tab , as well as adding some insight to Firebase projects

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